View limiting dial and ring structure for combination locks and the like
US4404823A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 1980 |
| Grant date | Sep 20, 1983 |
| Priority date | — |
| Expiry date | Dec 5, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T70/8378
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A combination lock dial and ring assembly for combination locks and the like for limited range top reading of the dial indicia by reflected light rays only, including a rotatable dial member having a circular dial portion and a knob formation projecting forwardly therefrom wherein the dial portion has a rearwardly facing annular indicia bearing surface adjacent its periphery provided with rearwardly facing dial graduations and mirror image reversed dial numerals thereon for reading along reflected light ray paths. The dial ring has a forwardly facing dial receiving cavity encircled by an integral shielding surround ring formation over a sufficient extent to exclude observation of the dial graduations and numerals laterally and below the dial portion and having an interruption of limited circumferential extent providing a sight opening for observation of the dial graduations and numerals in a restricted observation zone generally above and vertically aligned with the axis of the dial member. The surface of the dial receiving cavity rearwardly adjacent the dial has an arcuate light-reflecting mirror surface at least spanning the arcuate extent of said sight opening positioned to refl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.